Manufacture of a finely divided dry soaf product



Reissued Sept. 27, y l Y l i Re. "UNITED STATES 'PATENT QFFICE,

' ROBERT L. HOLLIDAY, OFNEW YORK, NY., ASSIGN'OR TO INDUSTRIL SPRAY-133m@ CORPORATION, 0F NEW YORK, N. Y., A CORPORATION OF DELAWARE.

MANUrAcrURlE or A rINnLr-nrvrnnn Das: sonl rnomrcr.

Original No. 1,621,508, dated March 22, 1927, Serial 110,102,880, led April 19, `19226, and in Canada. Intell 17, 1927. Application for reissue led .Tnly 21, 195W.` Serial-Ro. 207,548.

The present invention relates tothe manuribboned and dried. Different portions facture of a lnely divided dry soap product of the soap produced in this way show, in and has to do particularly with a manner the ordinary manufacturing run, a rather of preparingr the soap stock to Arender it wide variation in moisture content, In the I suitable for conversion into dry form and' ordinary processes'v the solidified soap is obthe conversion of such stock into dry form tained in the form of cakes', blocks, frag- M in such a manner thatall of the conditions ments or flakes. of the process are subject to accurate con-v To effect solidication of the soapand to Atrol, .produce the ultimate soap product 1n finely 1 In the common process f soap manufacdivided form Ifor use as powdered soap or ture the fats and .oils are saponified by the' for pressing into/'cakes it has vbeen proposed 55 action of a caustic alkali such as, for examto take the hot soap paste as it comes from ple, sodium-hydroxide. The usualpractice the boiling kettles, break it up into finely is to cook or boil the fatty material in the divided condition and letlit fall in this con-v 15 presence of a properamount of eaustic'madition through the atmposphere until the teria! until the desired reactions have taken particles or fragments of the soap .paste are 70 place. After the completion oftherb'iling solidified. The action which takes place is operation and any 'other treatment which largely a'coollng and solidifying action, but may be necessary, depending upon the charsome evaporation ofmoisture from the soa acier of the raw materials used, the kind of takes place by reason of its passage through, coap desired; etc...the hot semi-liquid soap the air and by reason of' the contained heat' 75 paste isl crutched t6; reduce it to a thorof the soap itself. The diliculty with this onu-lily mixed homogeneous mass and to inprocess is that,l in the short time available corporate uniformly into it any filler or for solidificaton and with the conditions added material Awhich may be desired in the that are attained in practical operation, the finished soap, after which the soap is placed soap does not, in fact, solidify satisfactorily 0 vin racks or frames Where it remains until it and, although the initial soap paste or solidiies. After solidification the blocks of is as heavy as can reasonably be produced' soap are slabbed and cut into cakes, the during the process of manufacture, the soap 3o cakes are surface dried to facilitate handling invariably masses and cakes in a moist conand-the dried calies are then pressed to put dition and is not produced as a relativelyA 86 them in condition for packaging. AIn .the fine powder composed of non-adhering parmanufacture of ltoilet soaps the dried cakes ticles. To aid in evaporating the -li u id are usually chipped to reduce them to flake from the soap paste it has been propose to 35 form and the flakes are milled with coloring subject the boiled soap to high pressure and matter, perfume, and the like, to produce a to heat it at such pressure, before admitting 90 uniform homogeneous soap which is then it to atmospheric conditions, to atemperaplodded to convert it into, a @OntinllOlJS ture well above its boiling temperature at bar which may be' cut into cakes of any atmospheric pressure. When this highly 4o length and then stamped or pressed 'as deheated soap is released to atmosphere a rsired. ,l tain amount of evaporation takes place due 96 A. particular diflculty in the soap manuto the excess of sensible heat contained in facturing process lies in effecting solidificathe vpaste over that which it can contain at tion of the soa A period of days is re.- atmospheric pressure. This process, howuuired for solidlfcaton of the soap in bulk. ever, is 'subject to the disadvantages 'ust In the manufacture 0f milled toilet eSoaps noted and is not successful in the produc- 100 solidicationof'the boiled soap is sometimes tion of a powdered soap; A

facilitated by placing the soap mass on an It "has further been proposed to. modify vendless belt which slowly conveys it through this vprfmes'g by introducing t0 the heated Nl ay drying chamber wherein air is circulated' soap paste as it is released to atmospheric about the soap until it is. reduced to solid conditions a quantity 0f Supa-heated steam 105 form in condition Tor milling. 1In the proordrying airfortlev purpose of effecting duction of soap flakes the soap stock is comthe necessary evaporation, and it has also monly solidified on rolls and scraped of or been proposed to heat the air of the room or prevents satisfactory collection chamber into which thesoapis sprayed to thus furnish an appropriate amount of heat toy effect the desired evaporation. These latter proposals have not proven successful 'for the reason that the presence in the room of the moisture evaporated from the soap of the soap inthe -form of a dry powder, in addition to the fact that no systematic control of humidity conditions and consequent mois- -turecontent in the finished soap product is obtainable; It has further beenl proposed to disintegrate or break up soap paste drawn from the boiling kettles into relatively small fragmentsand to drop these fragments of soap paste against and through a rising current of air to effect solidiication of the particles and thus to produce a dry soap product of granular nature made up of irregular particles or fra ments. This process is open to a number o objections such as the fact that the heavier fragments passthrough the apparatus in a shorter time and conse uently with less drying` treatment than o the lighter fragments with theresult that different portions of the/dried soap product contain rather widely dierent amounts of moisture, the loss of a large amount of the light4 soap fragments if the soap is disintegrated to reasonably fine condition and if any substantial amount of air'isused, the

variation of operating conditions due toV changes in atmospheric conditions and the practicalimpossibility of successfully qperating the process to satisfactorily pro uce a dry solid roduct under certain atmospheric conditions, summer days. This process is not at all successful 'if an attempt is made to heatthe treating air for the reason that the treated soa fragments time they leave Vthe appagatus so that it is practically impossible'to collect the particles in solidified state unless their water' content is reduced far below that which is desired in the finished soap.

It is a particular object of thisinvention to provide a process for the production of a powdered soap by which the soap can successfully be produced directly in the form of a dry, non-sticking powder offrelatively small particle size and of reasonably regular particle shape and structure and aving a moisture content which is readily controllable over a wide range amply covering a'll of the requirements of the various kinds of commercial soap products. Thisis accomplished in the present invention by the manner of p particu arly by the method which is employed in Areducingthel Soap stock toA solid form.

The initial soap stock is prepared in free flowing condition rather than in the form of such as on hot humid contact with the air at its;l hig est tempera-ture c at substantially`v the;

reparing the initial soap stock and :que

a' heavy semi-liquid paste as i's frequently done in the manufacture of soap. For instance, in a common method for the'. manufacture of soap the soap stock as it comes from the boiling kettles is, at say a temperture of 150 F., in semi-liquid condition and can not in a fair sense be said'to be free flowing. In the present process the soap stock is prepared with a water content sufficiently high s'o that it is free flowing and in such condition that it mayy readily be broken up into a.fine spray of liquid particles. of relatively uniform size and structure so that a corresponding degree of reasonable uniformity and regularity of particle size and structure in the' ultimate product is obtained. The spraying ordisintegrating of the liquid soap is preferably conducted at temperatures of from 150 to 250 F., and it is under such temperature conditions that the soap stock should be in liquid free flowing conditioit The essential requirement of this part of the process is that the soap bel reduced to a condition which is suiiiciently fluid ,5to permit breaking up of the liquid mass into the form of a'fine spray,th e particles Yof which are essentially liquid particles -of' the same general order of magnitude in size and of regular generally spherical shape similar to t e particles of-a sprayed liquid as contrasted with the beaten up or shredded particles or fragments of a heavy semi-liqiid paste wherein the particles are entirely irregular'in shape and do not tend deiiliitely ,toward any specific configuration.

Aftergtlie soap stock has once been disintegrated-iin proper fashion it is important that., it be treated in such manner as to prodluce thetype of solid product desired and to permit of Asystematic and controllable variation of conditions so that the character of the ultimate product in turn may be controlled. The present process accomplislies the drying and the solidification of the soap particles under definitely controlled conditions while the particles are maintained in suspension in a gas. A number of' requirements are necessary to accomplish these results. It is important that the particles of soap stock be treated .in a current of circulating gas which carries away the flows in such fashion ,that,when continued. operation of the apparatus hasv been established, the conditions of the process such` as humidity, temperature, state of dryness of l moisture evaporated from the particles and lll! particles so pelled through and out of the apparatus in va deiniteland regular manner. With this arrangement the gas first contacts with the soap particles at Substantially its highest temperature and last contacts with the soliditied soap particles at substantially its lowest vtemperature.` The particles under The process also provides for removing the treated soap particles together with the gas which carries them, as well as the moisture contained in it, from the drying tower in intermixed condition so that. collection of the dried particles may proceed as desired at a point removed from the hot drying tower. The collection problem is simplified by reason of the fact that all of thesolids may pass out of the drying tower at one p oint. In the matter of conditioning the air current in which the soap particles are' carried in suspension cooling gas may be admitted as desired alongthe length of the tower so that after 'the soap particles have been reduced'to a desired moisture content they may also he suitably reducedfin temperature to assure their production in' nonsticking form whereby the soap product will besa. fineiy divided regular apparently dry free flowing powder. The present process therefore provides for a uniform treatment of the particles of soap stock to produce a uniform product which may be.controlled topossess within reasonable limits any desired moisture content and which may he successfully and easily produced commercially at all times and in all weather conditions in the form of an apparently dry solid leasily handled powder product.l

The accompanying drawing illustrates more 'or less diagrammatically an apparatus in which 'the present process may he carried out as a continuous operation. rEhe soap stock, after having been produced in the usual coursev of the manufacture of the product and having been prepared with a suiiicient amount of water to adapt it for treatment by thepresent process, 'is delivered to a tank l provided with an agitator 2 driven continuously by motor 3 for the purpose of maintaining the entire body of stock inl a thoroughlyimixed homogeneous condition. The tank 1; is steam jackcted as indi-"ated at 4 for the purpose of maintaining the stock at a suitable temperature. The liquid stock from the tank 1 is passed tower in such fashion as .to

through line 5 into the drying tower 6. The breaking up or sprayingr of the liquid stock` into the form of smallu-niformly constituted particles is effected by means of spray nozzles 7 located'in the upper part of the drying tower 6 and arranged about the uniformly distribute the spray throughout the entire upper portion of the tower. In the apparatusl here shown in the flow of soap tothe nozzles 7 occurs due to gravity, and the breaking 'is effected by means of atomizmg air or steam'supplied to the nozzles 7 as indi- Vup of the material into the form -of a spray cated at 8. The drlying gas consists of at- 5 mospheric air Whic is heated in the furnace 9 and is-then passed into the upper portion of the drying tower 6 through a passage or duct l? The furnace 9 may, for' instance, be oil tired andthe air passing through it may be heated by causing it vto pass along one side of heat transferring surfaces which on the other side ar-e heated by direct contact with the products of combustion.V The heated air entering the upper portion of the ltower contacts with the atomized soap liquid issuing` from the 4spray nozzles 7 at substantially its hottest temperature and. while drying of the soap particles is taking place, the drying air, the soap particles entrained therein and the moisture absorbed in the air'pass downwardly through the drying tower in' a common direction of flow and pass out of the tower at the discharge opening ll in interthro-ugh the hoppers 17 at the bottom of the 5 collectors. A conveyor 18, which 'may be a screw conveyor. a pneumatic conveyor. or the like, is provided to receivethe solids coming from the collectors and convey them continuously into the barrel or other package or storage reservoir 19. Flhe iiow through the entire apparatus is established by means of a motor operated fan 20 positioned at the discharge side of the bag lili collector 16 and passing the gas drawn from the collectors to atmosphere through stack 21.

The particles of the sprayed liquid are carried in positive flow through the tower 6 by the drying gas, and thus every particle is subjected to the drying treatment for substantially the same length of time. Conditions in the tower are controlled by regulating the temperature and amount ofthe soap material passed into the tower and perature andl with this the temperature and amount of drying air conditions in the tower and particularly tol restrict the evaporating action at the point'. where the moisture content of the soap pa-r' ticles has been reduced to a desired amount and for the purpose of cooling vthe dried particles to lsuch extent as to render their collection in dry powder for'm feasible, a supply of coolin air may be admitted to the tower as in icated -at 22.- The tower may be designed for the admission of this cooling air at any one or more points along the length of the tower and, by way of example in the apparatus here shown, the cooling air is admitted near the bottom of the towerand consists of' atmospheric air introduced by means of the power vdriven blower '23. feasible t0 condition this air, as, flor instance, by heating to a certain degree before admitting' it' to the tower. v-At the bottom of the. tower 6 below the discharge opening -11 is a motor driven disintegrator 24 designed to receive any agglomeratels orV heavyA particles which may possibly be formed in commercialoperation. Such heavy particleswill not be drawn into the duct l1 but will drop into the disintegrator .24 where they will be immediately broken up and caught in the air currentl which is,

drawn 'into the disintegrator through the opening 25. This rapparatus furnishes a means for carrying out the present process as a continuous operation which requires no manual handling of the material from the initial raw stock to the finished powder prod uct and, for 'that matter, to package form' ready for shipping.

As an instance of a specific embodiment of the process which has been employed successfully in the manufacture of a powdered soap the following conditions are given: An ordinarv boiled borax laundry .soap was used. The soap stock was prepared hot, its temperature as passed to the spray nozzles being about 220 F. The stock was prepared with about 10% solidsf At this tein-` solid content the mixture was very 'Y fluid. In fact, a materially less amount of water and a lower prelieating temperature can readily beused without reducing the soap mixture to a consistency so thick as to be'objectionable.A For economy of operation it is the best practice to preheat the liquid soap stock to as high a temperature as feasible and to prepare it .with as low a water content as will permit the ready handling and breaking up of the injur In some` instances it may be material into a. suitable spray, these condi-l tions, of course, being regulated so as to be compatible with obtaining the' desired qualities in the finished product and,avoiding to the product. There is always a' sufficient range between the moisture content of the material as sprayed and that of.

the finished soap for the reason that toilet soaps, laundrysoaps and the like, usually contain only about 12% water in their coinmercial form. The physical factor which Setermines the amount of solids which can ityy of spraying or disintegrating the soap liquid into a proper spray.` lryVitli an. adequate preheating temperature soap stocks l having a solidcontent as high as '30% to 4G70 Vmay vunder certain conditions be suc` cessfully handled. The best results in reducing the soap stock to a proper spray have been obtained in an air or steam atoniizingI nozzle designed to(producel an umbrella-like spray. The object is to secure a finely divided uniform spray distributed uniformly across the space within the walls of the tower without substantial contact with the walls. The 'initial air temperature employed was 350 F., and the temperature inK the tower after drying ofthe material was substantially complete was 180 F. The initial air temperature is, of course, subject to a'certain amount of variation dependingon the relapresent in the soap assprayed is the pos- -sibi tive amounts of air and liquid 'supplied to the tower, the amount of moisture desired in the ultimate product, and the like. The final .temperature is in a sense dependent on the product and must be sutliciently low so that the product will not melt or be reduced to gummy or )sticky condition. vThe reduction in temperature between the upper and lower portions of the drying tower is due largely to the evaporation of the moisture from vthe material under treatment. instance herein referred to a small vquantity of atmospheric air wa`s employed as a. cooling medium.

The soap product produced under the conditions just stated is a. light free-flowing apparentlyy dry powder.. It is uniform in appearance, is of uniform texture, is soft to the feel and exhibits' complete freedom from particles of grit when rubbed between the fingers. vWhen drop ed into a pan of water the product is readily dissolved without caking or lurnping bv a slight agitation, and it-readily floats on the surface of the water.

In the specific izo The particles of the soap as they appear under the microscope tend generally toward spherical form although more or less distortion from this form is present in most of the particles. The particles are generally hollow and may roughly be described as heavy walledsoap bubbles from which the The substance of the particles is amorphous and continuous. Each particle is a unitary mass of material in contrast to a particle which is granular and which may be broken up into its composite parts. When the particles of the present .product are disintegrated under the microscope they break up into irregular fragments or plate-like pieces somewhat in the nature of the broken fragments of dried egg shells. rEhe particle structure is analogous to that of hollow glass particles or bubbles in which the material of the particle is 4continuous and when disintegrated breaks up into fragments whichA are obviously broken out of a. continuous mass which is itself unitary and 1s not in any sense an aggregate of component particles.

The present invention therefore provides a process for successfully producing commercially a dry, uniform, free flowing, floating, non-caking powdered soap, which process is continuous, requires a minimum of labor, makes possible accurate control of all conditions which affect the character of the product and is flexible in the sense that dif- 4ferent sets of conditions can be established in continuous operation to thereby produce `different grades of product.

l claim:

l. The process of manufacturing a soap product in powder form which comprises preparing a soap stock inthe condition of a reasonably free flowing liquid, spraying the said soap stock to present it in the form c of a uniformly distributed liquid spray made up of small liquid-drops of the same general order of magnitude in size and of generally globular form as in the case of true liquids as distinguished from the irregular fragments of a disintegrated pasty material, en-

training the drops of the sprayed soap stock in a downwardly flowing current of heated dryirg gas which positively carries and propels the said drops and the-particles of soap resulting therefrom downwardly through the apparatus in like manner and direction of flow until uniform drying thereof is complete and separating and collecting the particles of the finished soap product from the said current of drying gas. y

2. The process 'of manufacturing soap in powder form which comprises reparing the soap in the form of a free owing liquid stock, evaporating moisture from the liquid stock by spraying it inthe iform of fine drops into the initial portion 'of a current of heated drying gas which entrains substantially all of the said liquid drops and positively carries the said drops and the soap particles resulting therefrom along through the apparatus in like manner of flow while evaporation is taking place, whereby the said particles remain in suspension in the gas current until the'moisture content thereof is reduced to the desired value and then separating the I Said particles from the gas current and collecting them to vform a powdered soap product.

3, The process of producing a finely divided powdered soap product which comprises compounding the ingredients of the product to form a relatively free flowing stock, spraying the said soap stock in the form of small independent drops into a current of heated drying gas at substantially the hottest portion thereof to thereby effect drying of said drops, positively propelling the sprayed drops of soap stock and the dried particles of the soap product resulting therefrom` through and out of the drying apparatus by said current of drying gas, the said particles being carried in and by the said gas current whereby every particle is subjected to substantially identical treatment in passing through the drying tower and a uniform product is obtained, regulating the relative amounts and'temperatures of the liquid soap stock and the dryingigas to pro-f duce an ultimate product of the desired moisture?4 content and collecting the particles of the finished soap product from the current of reduced temperature spent drying gas issuing from the -drying-tower.

4. The process of manufacturing a soap product in powder form which comprises preparing a soap stock containing all of the ingredients of the ultimate soap product in condition sufficiently liquid so that it can be disintegrated to a reasonably uniform finely divided condition in suspension in a gaseous drying medium, effecting such disintegration in a current of heated drying gas` by atomizing to thereby effect evaporation of moisture from the said stock and reduce it to the form of solidified apparently dry particles in suspension in the said gas, producing a positive and controlled lmovement of the finely divided soap stock through the drying apparatus by entrainment thereof in the said current of the gaseous medium to thereby effect substantially uniform drying of the respective soap particles, the evaporation of moisture therefrom taking place while the material is in finely divided suspension in the gas, restricting the drying action when the material has reached an appropriate moisture content and reducing the. temperature of the particles of the'material to a degree appropriate for effecting solidification and facilitating handling by introducing ,to the heated gas current carrying the said particles in suspension a quantity of cooler gas and then separating and collect-- 5. The process of Inanufacturing a soap product in theI form of a powder wherein the component particles are of generally 5 liquid, spraying the said spherical shape which comprises preparing a.

soap and water solution having a relatively low percentage of solids so that the `said solution is free-flowing in the sense of atrue soap solution in the form-of fine generally heated drying gas .to e absorption of the maj or portion of the water content thereof, whereby the solids con- 10. tained in the respective sprayed drops of the said soap solution are reduced to-sub lobular drops into a ect evaporation andV frompgrit as 'evidenced by rubbing between" the fingers, is readily soluble in water and is; 'composed of soap particles which, as they;

appear under 'the microscope, are of generally rounded spherical orm, characterized by the substantial absence of angular formations. e

7. A soap spray Y dried product composed essentially of particles which'are generally spherical in shape and are characteristically hollow particles in the general nature of.

small heavy. walled soap bubbles from 30 which the moisture has been removed so that e .the bubbles assume a solidified substantially dry vform. L A In testimony whereof I ailix my' signa:

ture.

ROBERT L. HOLLIDA- Reissue: Paten: No. i 16,149. "iiatuqrch-z, i927, to

ROBERT L. HOLLI'DAY.

is hereby certified that error appears in the'printed .ape'cificilion of lthe above numbered patent requiring correction as follows: Page 1, lipe'lZl, for the misspelled word "coap" read "soap" and line 69. for theword-"tmposphere" read "atmosphere"; page 3', Vline 75, strike out the"word""in"; page 6,A line 26 claim 7, for. the words "LA soap spraydr.ed"'r'cad "A spray dried soap"; and that the said Letters Patent should be read with theae'corrections therein thatvthe I same may conform to the record of the casein the Patent O ffice.

Signed and sealed this 25th day of October, A. D. 1927.

i Acting Comi nionero" Patente.

y -Y l raler-@ AlMeile- REIS. 16,749.4120601'# L.- 'HoZZidaytNew York, N. Y.

DI'VIDED DRY SOAR PRODUCT.

MANUFAQI'URE or A FINELY- atent datedv September 27 ,1927. "Disclaimer file October 9, 1928, by'- the assignee, Industrial Spray Drying Corporation. Hereby enters this disclaimer to certain of thel process .claims oi the above identlfied reissue patent, na une ly, clai1ns` 1, 2, 3,'and 4, excepting when in the process y' clalmed the step of preparing the soap-stock involves adding water to the ordinary soap' 0j regular commerclal manufacture foi-@preparing the soap in the -form of-.a free-flowing liquidstock so that ltmay be sprayed intoV the for-m of line drops. i

[Oficial Gazette October 23,49%;1 a A 6 l v .16,74e

spherical shape which comprises preparing a. from grit as 'evidenced by rubbing between" soap and water solution having a relatively the fingers, is readily soluble in water and is; 20 low percentage of solids so that the `said composed of soap particles which, as they; Y solution is free-flowing in the sense of atrue appear under fthe microscope, -are of gen- 5 liquid, spraying the said soap solution in the erally rounded spherical orm, characterized form-of fine generally lobular drops into a by the substantial absence of angular :Eormaf heated drying gas .to eect evaporation andV tions. t 25 absorption of the major portion of the water 7. A soap sprayv dried product composed content thereof, whereby the solids conessentially of particles which'are generallyV 10. tained in the respective sprayed drops of spherical in shape and are characteristically the said soap solution are reduced to-sub. hollow particles in the general nature of` v stantially dry condition in generally spheri small heavy. walled soap bubbles from 30 cal. small independent shapes, and then which the moisture has been removed so that separating and collecting from the said gas .the bubbles assume a solidified substantially 15; the dried generally spherical soap particles. dry form. to orm the finished powder soap product. In testimony whereof I aiiix my' signa:

6. Ar'spray' dried soap product which is ture.

` light bulking, is oi unifornr texture, is free ROBERT L. HOLLIDAY.A

CERTIFICATE or coniuzc'noir-.f1V` reissue: Paten: ANo. 16,149. "Glnige-uqrchj27p i927, .to

aoBERrL. HoLLiDAY. l i

. is hereby certified that error appears in the'printed .ipe'cificition of lthe above numbered patent requiring correction as follows: Page 1, lipe'lZl, for the misspelled werd "coap" read "soap" and line 69. for the word"tmposphere" read "atmosphere; page 3', V'line 75, strike out the"word""in"; page 6,A line 26. claim 7, for. the words' "LA soap spraydr.ed"'r'ead "A spray dried soap"; and that the said Letters Patent should be read with these'corrections therein thetvthe I same may conform to the record ofthe case in the Patent O ffice.

Signed and sealed this 25th day of October, A. D. 1927.

. 9 n.1.-` Moore," LSeIl. y Acting Conminioneroff"Patents.

l DISQLAIMER--, v f-lf v. REIS. 16,749.R0bert L.- 'Holliday New York, N. Y. MANUFAQI'URE or A FINELY- ,DI'VIDED DRY SOAR PRoDUor'. atent datedv September 27 ,1927. "Disclaimer file October 9, 1928, by'- the assignee, Industrial Spray Drying Corporation. i Hereby enters this disclaimer to certain of thel process .claims oi the above identlfied reissue patent, narnely, clai1ns.1, 2, 3,'and 4, excepting when in the process clalmed the step of preparing the soap-stock involves adding water to the ordinary soap' 0j regular commercial manufacture foi-@preparing the soap in th -form of-.a free-flowing liquidstock so that itmay be sprayed intr'V the for-m of fine drops. i

[Oficial Gazette October 23,49%;1 a A 

